I am using Ubuntu for Windows Subsystem for linux with release CanonicalGroupLimited.Ubuntu18.04onWindows_1804 .

This release does not contain of course all the packages and what I am trying to do is install some packages I need, then with the new roofs create a new install.tar.gz and compress everything into a new appx file that will be then used to install Ubuntu for WLS on any windows 10 PC.

This goal here is reducing the time spent on upgrading every time the basic release and centralize the upgrade/maintenance of the system .

I have been successful at installing Ubuntu for WSL as a root user ( using the command ubuntu1804.exe install --root ) , upgrading and installing the missing packages like openJDK, curl etc … . Then I compressed the rootfs into an install.tar.gz and here comes my issue .

When I try to reinstall it with the new filesystem by running the ubuntu1804.exe, the shell prompt stuck at the step of creating a new UNIX username . No matter how many times I enter a username, it prompts the same thing again and again as you can see in the screen shot .